Method of preparing octahydro-phenanthridines



United States Patent "ice 3,408,351 METHOD OF PREPARING OCTAHYDRO- PHENANTHRIDINES Harry Chafetz, Poughkeepsie, and Edwin L. Patmore, Fishkil], N.Y., assignors to Texaco Inc., New York, N.Y., a corporation of Delaware No Drawing. Filed Aug. 25, 1966, Ser. No. 574,901 9 Claims. (Cl. 260-283) ABSTRACT OF THE DISCLOSURE A method of preparing 1,2,3,4,7,8,9,10-octahydrophenanthridines which are useful as corrosion inhibitors in oil and gas well fluids comprising contacting a 2-(1- cyclohexenyl) cyclohexanone with a hydrocarbyl amide in the presence of an acidic catalyst.

This invention relates to a method of preparing 1,2,3,4,7,8,9,10-octahydrophenanthridines of the formula:

Bl; i W 7 2 l l 8 1O where R is a substituent selected from the group consisting of hydrogen, alkyl, aryl, alkaryl and aralkyl of one to 20 carbons.

The octahydrophenanthridine products of the invention are useful in amounts of between about 0.5 and 5 wt. percent as corrosion inhibitors in oil and gas wells, and pickling acids. In the past, one method of producing octahydrophenanthridines called for the reaction of 2-(1- cyclohexenyl)cyclohexanone, an aldehyde and ammonia in the presence of catalyst. Although this method is quite effective in producing the desired octahydrophenanthridines, it has the disadvantage of utilizing relatively expensive aldehydes and further requires the employment of ammonia which due to its ready volatility requires special handling which further undesirably adds to the process expense.

We have discovered a method of preparing the octahydrophenanthridines as defined wherein the employment of ammonia is eliminated and the relatively less expensive amide reactant is substituted for the aldehyde reactant.

More particularly, the method of the invention comprises contacting 2-(l-cyclohexenyl)cyclohexanone with a hydrocarbyl amide of the formula:

0 R-ii-NHz where R is as heretofore defined in the presence of an acidic catalyst. Examples of acidic catalysts contemplated herein are the acidic metal oxides such as thoria, alumina, silica, silica-alumina, silica-thoria, alumina-thoria, and silica, alumina or thoria combined with minor amounts of e.g., between 5 to 40 wt. percent of chromia, magnesia, or boria and mixtures thereof. Additional suitable catalysts are the mineral acids such as sulfuric acid and polyphosphoric acid; strong organic acids such as toluene sulfonic acids and sulfonated divinyl-benzene crosslinked polystyrene resins; additional suitable acid materials are phosphorus oxychloride and phosphorus pentoxide.

Under advantageous conditions, the reaction is conducted at a temperature between about 80 and 375 C. in a mole ratio of amide to cyclohexenyl cyclohexanone of between about 1:5 and 5:1. However, when the catalyst is an acidic metal oxide as defined the reaction 3,408,351 Patented Oct. 29, 1968 should be conducted above about 220 C. Further when the catalyst is one of the sulfonated divinylbenzene crosslinked polystyrene resins such as the tradename product Amberlyst 15 the reaction temperature is preferably maintained below about 150 C. Amberlyst 15 is manufactured and sold by the Rohm & Haas Company.

The method is broadly described by the following equation:

where R is as heretofore defined. Referring to the above equation, it is to be noted that in cases where the amide R is other than pentyl there is produced in many instances along with the corresponding octahydrophenanthridine, 6-pentyl-1,2,3,4,7,8,9,lO-octahydrophenanthridine.

The method may be conducted under continuous or batch conditions. Under continuous process conditions the reaction is preferably conducted in the vapor phase with a mixture of the amide and cyclohexenyl cyclohexanone reactant passed over or through a bed of catalyst particles preferably of a size between about A and /2 utilizing a preferred average contact time of between about 1 and 10 seconds. The vapor phase reaction is normally conducted at a temperature above about 300 C. at atmospheric pressure, however, subatmospheric and superatmospheric pressures up to about 50 p.s.i.g. may also be employed. The quantity of catalyst employed in the vapor phase reaction in terms of liquid space velocity at 20 C. is advantageously between about 0.1 and 3 volumes reactant/volume catalyst/hour.

Under batch reaction conditions, the reaction is normally conducted in the liquid phase preferably with the continual removal of water. In order to facilitate water removal, an inert organic liquid (e.g., liquid hydrocarb0n) of a boiling point between about 60 and 225 C. which forms an azeotrope with water is desirably employed. Desirably, during the vapor phase reaction inert gas such as nitrogen is passed through the reaction zone to function as a carrier gas for the reactants and product. The quantity of inert gas employed in terms of space velocity calculated at 21 C. is advantageously between about 35 and 245 volumes inert gas/volume reactor occupied by catalyst/hour. Most preferably, the inert gas introduction is instituted prior to reactant introduction in order to flush out any air and thereby decrease the change of any undesired oxidation during the reaction. The liquid organic azeotroping agent advantageously constitutes between about 50 and wt. percent of the initial reaction mixture. Further, in the batch reaction, the catalytic materials employed normally constitute about 0.7 to 35 wt. percent of the reaction mixture. Still further, atmospheric pressures are normally employed but subatmospheric and superatmospheric pressures up to 50 p.s.i.g. may be utilized if desired to facilitate the removal of water or to maintain the reactants in the liquid phase, that is, prevent their escape from the reaction zone.

The octahydrophenanthridine product is recovered from the final reaction mixture by standard means such as fractional distillation, filtration, extraction, chromatographic separation and combinations thereof.

Specific examples of the amide reactants contemplated herein are acetamide, hexanamide, benzamide, formamide, capramide, lauramide, 4-ethylbenzamide, Z-ethylbenzamide and a-phenylacetamide.

3 4 Specific examples of the inert liquid organic azeotropvolume of the reaction tube occupied by catalyst (58 cc.). ing agents for water contemplated herein are toluene, TABLE Ia xylene, tetralin, dec'alin, benzene, mesitylene, n-nonane, Runs n-octane, cyclohexane, n-decane, and chlorinated solvents Description such as chlorobenzene, dichlorobenzene, chloroform and 5 B carbon tetrachloride. Reactants: V c

Specific examples of the octahydrophenanthridine prodfi gtggzz gfff i f i f fff jff ifg ucts contemplated herein are 1,2,3,4,7,8,9,lO-octahydrozi-e ciohexenynphen-anthridine, 6-phenyl 1,2,3,4,7,8,9,10 octaphenangfg g fg gfigg 35 thridine, 6 undecyl l,2,3,4,7,8,9,l0 octahydrophenan- 1O .ketone 2. 1 1.35. thridine, o heptyl 1,2,3,4,7,s,9,10 octahydrophenang 55 a} 350 thridine, 6-(4-methylphenyl)-1,2,3,4,7,8,9,l0 octahydro- N2 r ite,m1s./min., phenanthridine, 6-(2 ethylphenyl)-l,2,3,4,7,8,9,1O-0ctag f 3 g: hydrophenanthridine, 6-naphthyl-1,2,3,4,7,8,9,l0-oct-ahy- Conversion ketone react, drophenanthridine, and 6-phenylmethyl-l,2,3,4,7,8,9,lO- ggggf 96 33 79 octahydrophenanthridine. gctahydigipl enatithri- 1X18 1'0 110 Z The following examples furtherullustrate the invention B (yield, mole Methyl (13) Phenyl (2O), Hydrogen but are not to be construed as limitations thereof. percent)* pentyl (6). pentyl (9.5). 11).

Based on unrecovered cyclohexanone reactant. EXAMPLE I TABLE 1b This example illustrates the continuous, vapor phase Runs embodiment of the method of the invention. Description The following runs were carried out in a 1" x 24" D Reactants: Pyrex tube positloned vertically 11}, an electric tube fur Amide aummidenn Hexamide; nace having a heating area of 18 1n length. The tem- 2o Amide,g 39.8 23. 0.

, 2-(1-c clohexenyl eyclohexanone, 35.6- 35. perature was sensed by a thermocouple located external Mole iatm'amidg/ketone 1 L to the tube and extending from approxlmately the center React. cond.: of the heating chamber to the top. The tube was packed Temp-i 310 N2 t ,mJ 21 (3-. 34.... with a 6 layer of Berl saddles on the bottom, a 6 layer netigtf resirie r igsecs 4.9

. Conversion ketone react, etc nt. 52 56 9f pelleted catalyst of an average diameter of about 6 gmup 1'2,34'7,8,9,10mt1;hym 1n the middle and a 6 layer of Berl saddles on phenanthridine product: top. The tube was fitted at its upper end with an adapter -s p (y ld, mole percent) Ugg eg l P y comiected a pressure equahzmg .funnel and a system Based on unrecovet'ed cyclohexanone reactant. i for introducing a metered flow of nitrogen gas. The bottom end of the tube was connected to a receiver attached EXAMPIjE to a water cooled condenser followed by a trap cooled This example illustrates the liquid phase, batch, embod1- in a Dry Ice-isopropanol mixture. The catalyst pellets ment f the method f h inv ntiqn. employed were a silica-magnesia combination containing To a flask q pp With a mechanical 70-75 wt. percent silica and 25-30 wt, percent magnesia, thermometer, and water separator fitted with a condenser The prepared reaction tube was preheated at 450 40 Which in turn is Connected to a p cooled y a y C. for about one-half hour while being swept with a p p n mixture, there was g d amide reactant, stream of dry nitrogen and was allowed to cool to the y y cyclohexflllone, catalyst and a liquid desired operating temperature. The 2-(1-cyclohexenyl) hydrocarbon Water azootropmg agent h n u The cyclohex-anone and amide wer char ed t th tub f reaction mixture was heated for the required time at the a dropping f nn l during hi h i nitrogen was desired temperature with the continuous removal of water tinuously passed through the reactor in order to facilitate as v rh after hi h e hot ol tion was an the passage of a reactant therethrough and the recovery from the catalyst. The catalyst was'washed several times of the products therefrom. Th products were recovered with fresh solvent ethanol and the washings were added to in the cold traps and analyzed by gas chromatogra hy. the filtrate. The resultant mixture was then cooled and Specific test data and results of the runs using the any amide that precipitated was filtered and dried. Th above method are reported below in Tables Ia and 1b, filtrate was then distilled. Alternatively in some cases the In Runs A, B, C and E the catalyst consisted of reaction mixture was distilled without removing the amide. silica and 30% magnesia. In Run D it consisted of The final Products were analyzed y gas chromotographyr silica and 25% magnesia. The nitrogen rate in all runs The foreg lng procedure was repeated utilizing various save Run D was 235 mls/minute, Al in R D th 59 amide reactants, catalysts and liquid hydrocarbon azeorate was 34 mls/minute. Tables Ia and 112 are set forth troping agents as well as various reactant amounts and immediately below. The reaction time was calculated conditions. The test data and results are reported below inon the basis of volume of reactants at 310 C. and the Tables 11a to IId.

TABLE IIa Runs Description E F G Reactants and solvent: Amide Lauramide. Lanramide Lauramide.

Amide, grams 19.9 19.9 19.9. 2-(1-cyclohexenyl)-cyclohexanone, g 17.8 17.8..-- 17.8. Catalyst Amberlyst 15.. H2804 Polyghosphorlc Catalyst, g 5. ac! Solvent Solvent, mls Reactlon conditions:

Temperature, C 146448 -115 186-210. Reaction time, hrs 12 Conversion of ketone react., percent. 75 99 6-group1,2,3,4,7,8,9,10-octahydrophenanthridine product:

ti-group (yield, mole percent) Undccyl (60) Undecyl (30), Undecyl (35),

pcntyl (5). peutyl (27).

*B ased on converted cyclohexanone reactant.

TABLE IIb Runs D escription H I .T

Reactants and solvent:

Amide Benzamide.... Formamide. Lauramide.

Amide, g 2-(1-cyclohexenyl; cyclohexanone, g- 89 Based on converted cyclohexanone reactant.

TABLE 110 Runs Description K L M Reactants and solvent- Amide"... Acetam1de- Acetamide. Acetamide. Amide, g 17.7 17.7-. 7.7. Z-(I-cyclohexenyl) cyc 53.4.. 53.4 53.4. Catalyst POCl P p-Toluene sulfonic acid.

We claim: selected from the group consisting of alumina, silica, 1. A method of producing an octahydrophenanthndrne thoria, silica-alumina, silica-thoria, thoria-alumina, silicamagnesia, silica-5 to wt. percent boria, alumina-5 to 40 wt. percent chromia, alumina-5 to 40 wt. percent magnesia, alumina-5 to 40 wt. percent boria, thoria-S to 40 wt. percent magnesia, thoria-S to 40 wt. percent chromia,

sulfonated divinylbenzene crosslinked polystyrene resin,

thoria-S to 40 wt percent boria, p-toluene sulfonic acid,

sulfuric acid, polyphosphoric acid, phosphorous oxychlo- Catalyst,g- 35 35 S0lvent.... Tetralin-- Tetra Tetralin Solvent, m1 200 200 200. Reaction conditions.

Temperature, C 147-179 146466 160-177. Reaction time, hrs 6.7 10.3 15.0. Conversion of ketone react., percen 66 66. 6-gr0up1,2,3,4,7,8,9,IO-Qctahydrophenanthridine product:

G-group (yield, mole percent) Methyl (20)... Methyl (18)... Methyl (8).

Based on converted cyclohexanone reactant.

TABLE 11d Runs Description Reactants and Solvent:

Amide Lauramide Lauramide. Amide, g 39.8 19.9. 2-(1-cyclohexenyl) cyclohexanone, g.- 35.6 17.8.

atalyst p-Toluene sul- Amberlyst 15.

ionic acid. Catalyst, g. 0.5 5. Solvent Solvent, mls. Reaction Conditions:

Temperature, C 230-264 230-275. Reaction time, hrs 10.6. Conversion of Ketone React, percent 84 96 fi-g'rcup-1,2,3,4,7,8,9,lfl-octahydrophenanthridiue product:

o-group (yield, mole percent)- Undecyl (20), Undecyl (l7),

pentyl (21). pentyl(21).

Based on converted cyclohexanone reactant.

of the formula: 5 to 40 wt. percent chromia, s1l1ca-5 to 40 wt. percent where R is selected from the group consisting of hydrogen and alkyl, aryl, alkaryl and aralkyl from 1 to 20 carbons comprising contacting a mixture of 2-(1-cyclohexenyl)-cyclohexanone and an amide of the formula: 7

ride and phosphorus pentoxide, said temperature being maintained above about 225 C. when said catalyst is the non-phosphorus metal oxide.

2. A method in accordance with claim 1 wherein said contacting is conducted under batch, liquid phase conditions, said catalyst is present in an amount between about 0 0.7 and 35 wt. percent and said amide is contacted with said cyclohexanone in a mole ratio of between about 1:5

and 5:1.

where R is as heretofore defined at a temperature of be- 3. A method in accordance with claim 1 wherein said tween about and 375 C. in the presence of a catalyst 5 contacting is conducted under continuous vapor phase conditions at a temperature of at least about 300 C., said catalyst being present in an amount of between about 0.1 and 3 volumes reactant/volume catalyst/hour, and said amide is contacted with said cyclohexanone in a mole ratio of between about 1:5 and 5:1.

4. A method in accordance With claim 3 wherein said catalyst is a silica-magnesia combination.

5. A method in accordance with claim 4 where R is pentyl.

6. A method in accordance with claim 2 wherein said catalyst is polyphosphoric acid and R is undecyl.

7. A method in accordance with claim 2 wherein said catalyst is p-toluene sulfonic acid and said R is undecyl.

8. A method in accordance with claim 2 wherein said 8 7 catalyst is sulfonated divinylbenzene crosslinked poly styrene resin and said R is undecyl.

9. A method in accordance with claim 2 wherein said reaction is conducted in the presence of a liquid hydrocarbon water forming azeotroping agent having a boiling point between about 60 and 225 C.

References Cited UNITED STATES PATENTS 3,250,706 5/1966 Kuhn 260283 X NICHOLAS S. RIZZO, Primary Examiner.

D. G. DAUS, Assistant Examiner. 

